為釐清潛變效應在熱循環拘束限制下之角色及對循環應力–應變反應之重要性，本文延伸Lee之等溫增量式內涵時間黏塑性理論到變動溫度增量式計算法(Endo)。選用Sehitoglu對1070鋼在各溫度下之循環應力-應變遲滯曲線，建立含青脆化反應之核心函數及材料函數對溫度之關係式。再利用變動溫度增量式(Endo)，進行循環應力-應變計算，其結果與實驗數據相當符合。
再由Valanis和Lee之變形動力學潛變理論(DK)及Sehitoglu對1070鋼之潛變實驗(differential creep tests)數據，決定部分DK之材料參數，結合前述兩理論為Endo/DK計算法，配合部分拘束熱循環數據，可決定全部之材料參數，並建立材料參數對溫度之關係式。
利用Endo/DK及Endo計算法，分別對1070鋼在 (1)部份拘束(2)完全拘束(3)過度拘束之熱循環下進行應力-應變反應之計算。兩方法在三種拘束條件下之應力及非彈性應變範圍皆與實驗數據相當符合，但Endo無法預測平均拉應力之數據，而Endo/DK對平均拉應力在部分拘束下有準確之預測，完全拘束中低估了40%，過度拘束中高估了30%。由上述結果可證明在高溫受拘束環境底下必須考慮潛變效應以描述應力鬆弛現象。

In order to clarify the role of creep effect in the thermal cycles with constrains and the cyclic stress-strain response, this thesis extends Lee’s incremental Endochronic viscoplasticity under isothermal into non- isothermal condition (Endo). From Sehitoglu’s isothermally cyclic stress-strain hysteresis loops of 1070 steel, the kernel function including blue shortness of steel and the temperature dependent-material function are then established. The cyclic stress-strain computational results using Endo are in very well agreement with the experimental data.
According to Valanis and Lee’s creep theory of Deformation Kinetics (DK)and data provided by Sehitoglu’s differential creep tests on 1070 steel, material parameters in DK can be, at first, determined only at few testing temperature. Then their temperature-dependent functional forms can be completely determined by using the combination of computational method (Endo/DK) and the data of thermal cycles with partial constrain.
Employing the Endo/DK and the Endo only on thermal cycles of 1070 steel with (1) partial (2) total (3) over constraint conditions, the results of both methods on cyclic stress-strain response are in good agreement with experimental data in the sense of stress and inelastic strain range. In the prediction of cyclic mean stress, the results of Endo can not predict the tensile cyclic mean stress, but the result of Endo/DK under partial constrain can agree with data, however, underestimate 40% and overestimate 30% of tensile mean stress are found in the total and over constraint condition respectively. These results indicate that the creep effect must be involed in the thermal cycles with constrain to take care of relaxation phenomenon.

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